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57 Cards in this Set
- Front
- Back
periventricular nucleus secretes: |
antidiuretic hormne |
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actions of ADH secretion |
increase blood volume increase blood pressure increase conservation of total body water |
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adenohypophysis is in what anatomical region |
anterior pituitary |
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actions of ADH are: |
increase blood pressure increase total body water increase blood volume |
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ADH is also known as |
vasopressin |
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ADH is secreted in response to |
decrease in blood pressure INCREASE IN PLASMA OSMOLARITY |
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what are the actions of oxytocin (2) |
induces uterine contractions - via stretch reflex in the uterine wall promotes milk secretion |
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what does the supraoptic nucleus secrete? |
oxytocin |
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what are the effects of oxytocin |
stimulates uterine contractions promotes milk ejection |
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hormones that influence growth are |
GHRH - growth hormone releasing hormone GHIH - growth hormone inihibiting hormone |
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Other factors that influence growth are |
thyroid hormone insulin androgens and estrogens |
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what are the growth hormone actions (GH) |
hypertrophy - increase in cell size hyperplasia - increase number of cells |
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hormone classification of ADH (chemical property) |
hydrophillic peptide hormones (lipophobic) therefore requires protein carrier to enter cell |
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where does the growth hormone (GH) exert its effects in development |
on the epiphyseal plates (cartilage plate at each end of the long bone) |
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explain the process of GH release |
1) hypothalamus - growth hormone releasing hormone (GHRH) 2) endocrine cells in the anterior pituitary 3) stimulates release of growth hormone (GH) 4) goes in to the systemic circulation to target cells |
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what is the endocrine system and what is its function |
the endocrine system are glands or a group of cells that specialize in the synthesis and secretion of hormones to produce responses in the target cells to coordinate the body's systems |
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explain the process lipophobic or hydrophillic hormones exert there influence on cells |
1) messenger hormone needs to bind to a G-protein receptor 2) this activates a G-protein subunit which disassociates and activates adenylate cyclase 3) adenylate cyclase assists in conversion of ATP to cAMP 4) cAMP activates protein kinase A 5) protein kinase A activates proteins which provoke the desired cellular response |
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explain the process of hydrophobic or lipophillic hormone signalling |
messenger hormone binds to a hormone receptor complex (HRC) is carried into the cell via HRC HRC binds to hormone receptor element (HRE) on DNA strand activates transcription of MRNA MRNA moves into cytoplasm MRNA translated by ribosome unit to protein |
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example of hydrophillic hormones |
ADH catecholamines |
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examples of hydrophobic hormones |
steriod hormones -androgens, estrogens, progesterone thyroid hormones - T3 and T4 |
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what are the effects of alcohol on the ADH |
decreases ADH therefore increases polyuria leading to dehydration and subsequent hangover |
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what is a tropic hormone |
it is a hormone that controls the release of other hormones -e.g. tropic hormones secreted by the hypothalamus |
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what is located within the colloids in the thyroid gland |
iodine, thyroglobulin and enzymes |
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what is the functional unit of the thyroid gland and what does it do |
the functional unit = follicle serves in the production of T4 and T3 (t3 = triiodothyronine t4= tetraiiodothronine or thyroxine) |
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what is thryroglobulin |
it is a glycoprotein needed for the synthesis of T3 and T4 (precusor) |
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what does the parathyroid gland secrete |
calcitonin |
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what is MIT |
mono-iodo-tyrosine |
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what is DIT |
di-iodo-tyrosine |
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what coupling needs to take place to form t3 what coupling needs to take place to form t4 what is this process needs to take place in order for this "coupling" process to take place |
t3= MIT+DIT
t4= DIT + DIT iodination of tyrosine or thyroglobulins |
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which is more potent T3 or T4 |
T3 |
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what is the cause of hypothyroidism and what are the consequences |
thyroid hormone deficiency due to under active thyroid gland - may be due to lack of iodide in diet. Decrease BMR, increase fatigue, increase weight gain, sluggish mental state. |
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what are the causes of hyperthyroidism and what are the consequences |
excessive production of thyroid hormone may be due to tumors, thyroid stimulating immunoglobulins results in weight loss, tachycardia. heat sensitivity |
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what does the thyroid gland feedback to in order to regulate production |
thyroid gland feeds back to BOTH the anterior pituitary to decrease thyroid stimulating hormone (TSH) as well as the hypothalamus to decrease thyrotropin releasing hormone (TRH) |
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how will lack of iodine impact thyroid production |
will decrease thyroid production as it is needed for the formation of T3 and T4 |
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which endocrine organ houses the chromofin cells |
chromofin cells = adrenal glands |
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what does the adrenal cortex secrete |
the adrenal cortex is responsible for the secretion of glucocorticoids, mineralocorticoids, adrenocorticoids and sex hormones |
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what are the 3 layers of the adrenal cortex |
zona glomerulosa zona fasiculata zona reticularis |
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the zona glomerulosa secretes which hormone |
it secretes mineralocorticoids -primarily aldosterone |
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what does the zona fisiculata and reticularis secrete |
glucocorticoids and sex hormones -primarily cortisol and androgens respectively |
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what are commonality between ADH and aldosterone |
both will increase reabsorption of water in kidneys' collecting ducts both hormones will increase blood volume and blood pressure |
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ADH vs antidiuretic hormone |
ADH is a peptide hormone produced in hypothalamus causes re-absorption of water in the distal convoluted tubules and collecting ducts of the kidney Aldosterone is a steroid hormone produced in the adrenal cortex causes water and sodium re-absorption in the distal convoluted tubules and collecting ducts of kidney causes conservation of sodium and secretion of potassium inceasing water retention (where na goes water will follow) and increase blood pressure |
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main actions of the aldosterone system are: |
Na reabsorption K secretion blood pressure regulation via the renin-angiostensin-aldosterone system |
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explain the renin-angiostensin-aldosterone system |
decrease in renal perfusion release of reinin - converts angiotensinogen to angiosteinsin 1 - ACE in lungs convert to angiosteinsin 2 - stimulates aldosterone secretion in kidneys, posteriod pituitary, increases simpathetic activation |
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What is hpa |
Adrenocorticotropic hormone |
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What is CRH |
Corticotropic releasing hormones |
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Explain the glucocorticoid secretion process |
Triggered by stress or circadian rhythm. Activates hypothalamus which secretes CRH travels to target cells in the anterior pituitary triggering release of ACTH. This triggers the release of cortisol via the Zona Fisiculata and reticulatis in the adrenal cortex. |
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what are the actions of glucocorticoids
|
energy mobilization adaptive response to stress at low levels assists with anti-inflammation required for growth hormone secretion |
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2 pathologies related to hypo or hyperscretion of glucocorticoids are: |
cushing's syndrome (hypersecretion) addison's disease (hyposeretion) |
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epinephrine actions include
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fight or flight response -bronchiodilation -pupil dilation -blood shunting to heart, lungs and muscles energy mobilization |
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which two hormones secreted by the thyroid gland assist with calcium regulation |
calcitonin calcitriol - form of vitamin D |
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what is the influene of calcitrol
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-increases ca absorption in GI and renal reabsorption
|
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what is the infuence of PTH on calcium reabsoption
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stimulates bone reabsorption increases calcium reabsorption in the kidneys activates calcitrol increases calcium absorption at the digestive tracts |
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what are the actions of calcitonin on plasma calcium
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calcitonin has opposite effects of calcitrol and PTH. 1)stimulates bone deposition 2) increases excretion of calcium at the kidneys |
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what is the chemical formulation of vitamin D3 after conversion to calcitrol |
1-25-(OH2)D3 D3 = cholecalciferol |
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hormones effecting calcium resorption or calcification in bone |
parathyroid hormone
calcitonin |
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hormones effecting calcium absorption in the digestive tract are |
calcitriol or 1,25-OH2-D3 and PTH -small effect |
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hormones effecting calcium reabsorption in the kidneys are |
PTH stimulates reabsorption Calcitonin inhibits reabsorption calcitriol stimulates reabsorption |